Background: During the German division, two culturally very similar populations were exposed to very disparate socioeconomic conditions, which converged again after 1989. The impact of healthcare and life circumstances on mortality differences can better be estimated when cultural explanations are widely neglectable.

Objectives: For the first time, we analyse harmonised cause-of-death data explicitly by age. Hereby, we can show which ages or birth cohorts were particularly affected by German division and reunification in their mortality and to which causes of death this is attributable.

Materials and methods: We harmonised the German cause-of-death statistics by applying an internationally standardised harmonisation process to account for differences and breaks in cause-of-death coding practices. We analysed the data using decomposition methods.

Results: During the 1980s, east-west disparities were increasing as progress in the reduction of cardiovascular mortality was much stronger in West Germany, notably at older ages. After 1989, East Germany was able to catch up to the west in many areas. This is especially true for elderly persons and women, while east-west disparities are still visible today, particularly among male adult cohorts (1950–1970) strongly affected by the East German transition crisis.

Conclusions: The lower life expectancy of the East German population in the late 1980s was primarily caused by a slower pace of the cardiovascular revolution. The remaining present-day disparities are rather an aftermath of the East German transition crisis than direct aftereffects of the division.